Skiving-machine.



No. 632,990. Patented Sept; |-2,- I899.

B. F. DPNHAM. SKIVI NG MACHINE. (Application filed Aug. m,' 1898.) v (NoModel.) 3 Sheets-Shat l.

No. 632,990. I Patented Sept. l2, I899.

B. F. DUNHAM.

SKIVING MACHINE.

(Application flied Aug. 16, 1898.)

(No Model.) 3 Sheets-Sheet 2.

No. 632,990. Patented Sept. i2, i699.

B. F. DUNHAM.

SKIVING MACHINE.

(App canon filed Aug. 16, 1898.; (No Model) 3 Sheets-Shut 3,

NITED STATES PATENT OFFIcE.

BENJAMIN F. DUNHAM, OF BROCKTON, MASSACHUSET"S, ASSIGNOR TO THE'A'MAZEEN MACHINE COMPANY, OF BOSTON, MASSACHUSETTS.

SKlVlNG-MACHINE.

SPECIFICATION formingpart of Letters Patent No. 632,990, dated September12, 1899.

Application filed August 16, 1898. Serial No. 688,702. (No model.)

To (tZZ whom it may concern:

Be it known that I, BENJAMIN F. DUNHAM, of Brockton, in the county ofPlymouth and State of Massachusetts, have invented certain new anduseful Improvements in Skiving- Machines, of which the following is adescription sufficiently full, clear, and exact to enable those skilledin the art to which it appertains or with which it is most nearlyconnected to make and use the same.

This invention has relation to that kind of skiving-machines in which arotary knife and a rotary feed-rollare employed and which areparticularly adapted to skivin g upper-leather.

Experience with the class of machinesmention ed has demonstrated, amongother things, that it is desirable, and, indeed, essential, when perfectwork is to be done, that the rotary knife-support should be equippedwith means whereby its tip or inclination can be easily and readilyadjusted with nicety or exactness by persons of quite ordinary skill,and that the rise and fall of the presser-finger, in the performance ofwork on the machine, should be on a line parallel with the surface ofthe feed-roll, and also thata grinder for the knife, connected with theknife, should be provided, so that the knife when it becomes dull may bereadly sharpened by the operator. It is the object of my invention toprovide improved means for accomplishing these ends, all as I will nowproceed to describe and claim.

Reference is to be had to the annexed drawings and to the letters markedthereon, forming a part of this specification, the same lettersdesignating the same parts or features, as the case may be, whereverthey occur.

Of the drawings, Figure 1 is a front elevation, parts being representedas broken away, of a leather-skiving machine embodying my invention.Fig. 2 is a sectional plan view of the machine shown in Fig. 1, butshowing a different form of grinder from that represented in saidFig. 1. Fig. 3 is an end view of the knife or cutter and grinder andtheir supports and the immediate connections of the same. Fig. l is asectional detail plan View of the improved means for adjusting the tiporinclination of the knife. Fig. 5 is a side view of detached modifiedparts relating to the grinding means. Fig. 6 is a side view of Fig. 2,illustrating the relationship of the grinder to the knife, but notshowing the grinder-operating means further than the pulley on the lowerend of the rotary grinder stud or shaft.

My improvements have been wrought upon that type of leather-skivingmachines commonly known among shoemaking artisans as the Amazeenskiving-machine, and particularly upon the form of the Amazeen machineas heretofore modified by me, as shown in United States Letters Patentgranted to me July 13, 1897, so that the parts which have no modifyingeffect upon and are not directly connected with my improvements need notbe explained in detailas to their construction and mode of operation.

In the drawings, a designates the bed of the machine, suitably supportedand itself supporting theframework of the machine.

b is the feed-roll shaft, (which is also the main driving-shaft,) and cis the feed-roll.

dis the counter-shaft, the journals of which are supported byspring-pressed means to keep taut the belts (not shown) on the pulleys.

e is the rotary knife or cutter, supported in or by means which arepivoted to the lower forward end of the overhanging armfof the slidingframe g, the pivoting-point being in the cutting-plane of the knife andon a line running directly rearward through its axis.

Hinged or pivoted to the knife-shaft support near its upper end, as ath, (see Figs. 2 and is a short rod 1', the outer end of which is screwthreaded and is tapped into the thumb-nut j, having a rotary bearing ina stud k, projecting from the overhanging arm f. With this constructionby the turning of the nut j it will be seen that the knife-shaft and itssupport and the knife carried by the shaft may be tilted in onedirection or the other with respect to the surface of the feedroll so asto vary the inclination of the cut, as may be desired, and that thisadjustment of the knife may be effected by ordinarily-skilled mechanicswith great nicety and exactness. The adjustment of the knife, asdescribed, is necessary in order to effect a cut parallel with the faceof the feed-rollc or at a less orgreater angle thcretoin order that astunted, inclined, or straight scarf may be tnade.

Z designates the grinder, consisting of a disk of emery or othersttitable tnaterial mounted on the lower end of a rotary shat't an,which is supported in bearings connected with the knife-shaft support,so that when once the grinder is adjusted to proper position relativelyto the knife it will retain that adjustment however the knife may beadjusted that is to say, the knife and grinder will be adjusted inunison so far as sttch adjustment may relate to their inclination. Thisis important, since all that is necessary when the knife is to be groundis to set the grinder down into contact. with the knife and put theknife and grinder in motion.

The grinder-shaft m is supported principally in the bracket 71, attachedto the knifebracket, as at o, insuring that both move in unison whenadjusted with respect to their inclination, and the grinder-shaft isprovided with a pulley p, which may be driven by a belt passingthereover and over a pulley g on the counter-shaft.

Instead of connecting the grinder with the knife-bracket I may make itindependent thereof, as is shown in Figs. 2, 5, and 6, which show thegrinder mounted on a stud 7', adjustable in its support and the latteradjust-able on an arm 8, which carries the said support. The stud -r isprovided on its lower end with a pulley t, which may be driven by abeltpassing around it, double pulleys a, double pulleys o, and a pulley wonthe counter-shaft (l. The arm sis pivoted upon the frame, as at 0;, (seeFig. 2,) so that when not in use it may be swung back under the frameand out of the way, and when so swung back the belts for driving thegrinder will be slackened to such an extent as to stop the rotation ofthe grinder. This operation occurs from the fact that the pulleys a aresupported by the arm 8 on a stud which moves concentric with the pivotalstud 00, on which the said artn is pivoted. bring the grinder intooperative position with relation to the knife, the belts will betightened upon their pulleys, and when swung inward out of the way thesaid belts will be slackened, so that they will not operate to drive thegrinder. It will be observed that the relationship between the pivotalaxis of the supporting-arms and the plane of the rotary grinder and therotary knife is such that as the grinder is swung away from or againstthe knife there is no change in its inclination relative to the plane ofthe skivingknife. This is an important feature, since no matter howsmall the knife may become Worn, thereby making it necessary to swingthe grinder through a longer are than when the knife is full size, theinclination of the grinder to the knife is not affected as it would beif the movement of the pi voted arm toward or away from thecutting-knife caused any When the arm 3 is swung outward tov variationin the inclination of the grinder and its axis. Moreover, by thisconstruction the grinder is moved bodily away from the vicinity of theknife, so as to leave the space about the knife clear and unobstructed.In Fig. 6, for the sake of avoiding confusion, only the pulley t on thelower end of the stud or shaft 7' is shown as the means for operatingthe grinder. It will be understood with reference to this figure thatwhen the grinder is in fullyoperative position it will be inclinedlyadjusted on the arm .9, so as to bring its surface into contact with theedge of the blade.

I am aware that a readily-operated thumbscrew for operating theknife-bracket to tilt or incline the knife and the provision of meansfor connecting the grinder shaft bracket with the knife-shaft bracket,so that both may be adjusted in unison, have been contrived andapplication for a patent therefor made by Charles H. Bayley, of Boston,and hencedo not herein claim such means broadly. I

As heretofore, in order to properly feed the material to be skived tothe knife, I employ a feed-roll, a cooperating feed-disk partlyoverhanging its outer edge, an edge-gage overhanging its inner edge, anda horizontal presser-finger projecting over the surface of the rollbeyond the edge-gage. I have, however, introduced a novel feature bymounting said presser-finger so that however much it is lifted from thesurface of the feed-roll in order to accommodate different thicknessesof leather both ends have the same extent of movement away from thesurface of the feedroll, so that the pressure exerted upon the leatherby the outer end is just the same as the pressure exerted at the innerend and at all intermediate points when the finger is in any givenposition. This is an important feature, since heretofore in this classof machines the horizontal presser-finger has been so mounted that theouter end was raised more than the inner end, so that as the finger wasraised little or no pressure was exerted upon the leather at the outerend. I have shown in Figs. 1 and 2 of the drawings one mode of carryingthis idea into effect. As therein shown, the presser finger or bar '0 issupported by a suitable part of the machine from the same side of thefeed-roll as the edgegage and projects out beyond said edge-gage overthe feed-roll, so as to hold down the stock in place upon thesurface ofthe roll, it being assisted in this function by the tension-spring .2,whose action is regulated by the tensionadjusting screw .a.. Theresser-finger has at its rear end an angular extension or arm I), whichis pivotally connected with a part of the machine. In this instance boththe edgegage and thepresser-finger are shown mounted upon the slidingframe g, so that they are movable in unison therewith. A spring 0,secured at one end to the pivoted stud d and at its other end to thepresserfinger, serves to press the finger down toward IIO the roll. Itwill be observed that the movement of the finger to or from the roll isnot accompanied by any longitudinal tilting or inclination of saidfinger with relation to the surface of the roll, since from end to endof the operative portion of the finger all points have an equal degreeof movement from the roll, and hence the finger when in any givenposition exerts a uniform pressure upon the leather throughout itslength, as explained above. In the form of construction shown in thedrawings this effect is due to the fact that the pivotal axis of thepresser-finger is parallel to the axis of the feed-roll; but theessential thing is that the upward movement of the finger from thefeed-roll shall not be accompanied by any disturbance in a longitudinaldirection of the parallelism between the finger and the feed-rollsurface, thereby securing a uniform pressure upon the leather at allpoints along the operative portion of the presser-finger.

As before stated, such parts of the machine as have not been changed inmaking my improvements, and the functions of which are well understoodby 1eather-working artisans, have not been described in detail becauseit has been thought unnecessary.

Having thus explained the nature of the invention and described a way ofconstructing and using the same, though without attempting to set forthall of the forms in which it may be made or all of the modes of its use,it is declared that what is claimed is- 1. In a leather-skiving machine,the pivoted knife-carrying bracket, combined with a screw pivoted at oneend to said bracket, a relatively-fixed part of the machine, and athumb-nut having a bearing in the latter and engaging said screw.

3. The combination, with the pivoted knifecarrying bracket and theframework of the machine, of a horizontally-arrauged screw pivoted tothe bracket, and a thumb-nut having a bearing in the framework andadapted to engage the said screw.

3. In a leather-skiving machine, the combination, with the framework ofthe machine, of an arm pivoted to swing toward and away from thecutting-knife, a rotary grinder carried by said arm and movable with itagainst or away from the cutting-knife, an idler-puL ley rotatablymounted near the pivotal point of said arm, and a pulley mounted on therotary grinder-shaft in position to receive a belt passed from saididler-pulley.

4. In a leather-skiving machine, the combination, with the framework, ofa rotary knife, a rotary grinder mounted on a supporting-arm, said armbeing pivotally connected with the framework to carry said grinderbodily toward or away from said knife without varying the inclination ofsaid grinder with relation to the plane of said knife, substantially asdescribed.

5. In a leather-skiving machine, the combination, with a rotary knife,of a rotary the pivoted resser-finger, and a tensionspring for normallypressing the same downward bodily, whereby when the presser-finger israised it will be raised on a line parallel with the surface of thefeed-roll.

8. The combination, with the frame of the machine and the feed-roll, ofthe presser-finger having an angular part pivoted to the frame, and atension-spring for pressing the presser-finger down bodily.

9. In a skiving-machine, the combination, with the feed-roll, of apresser-finger pivoted to move about an axis substantially parallel withthe axis of the feed-roll and means for yieldingly pressing thepresser-finger toward the surface of the feed-roll, substantially asdescribed.

10. In a skiving-machine, the combination, with the feed-roll arrangedto rotate about a horizontal axis, a presser-finger pivoted upon ahorizontal axis lying outside of the vertical plane of the feed-rollaxis, whereby the pivotal movement of the presser-finger does notdisturb the longitudinal parallelism between the operative part of thepresserfinger and the surface of the feed-roll.

11. In a skiving-machine the combination of the cylindrical feedroll,the feed-disk, the edge-gage and the overhanging presserfinger movablein unison, said presser-finger having also an independent upwardmovement from the feed-roll without disturbing its longitudinalparallelism to the feed-roll surface.

12. In a skiving-machine the combination with a feed-roll, of afeed-disk partly overhanging one edge thereof, an edge-gage overhangingthe other edge thereof, and a presserfinger projecting horizontallybeyond said edge-gage and longitudinally of the roll, saidpresser-finger having a yielding movement away from the roll withouttilting longitudinally with relation to the surface of the roll, wherebythe finger is caused to exert a uniform pressure throughout the lengthof its operative portion, substantially as described.

In testimony whereof I have signed my name to this specification, in thepresence of two subscribing witnesses, this 28th day of July, A. D.1898.

BENJAMIN F. DUNIIAM.

IVitnesses:

HERBERT H. CHASE, llIARIA P. DUNHAM.

